Improved Image Parser Regex & public logging

- Parser logging methods are now public. This should help integrate
proper logging on custom parsers.
- Parsers now reuse the same regex pattern for efficiency
- Regex pattern changed to match all kinds of image resolutions.
(Thanks to:
http://stackoverflow.com/questions/26050551/java-regex-ignoring-size-string-in-image-url/26050611
)